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Peutz-Jeghers Syndrome

Peutz-Jeghers Syndrome

Peutz-Jeghers syndrome (PJS) is an autosomal-dominant inherited disorder characterized by GI polyps and mucocutaneous-pigmented macules. Peutz-Jeghers syndrome is 1 of the polyposis syndromes, a group of inherited or acquired conditions characterized by the growth of polyps in the GI tract and associated with other extracolonic features. The syndromes are caused by mutations in specific genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure associated with tumor Tumor Inflammation- suppression Suppression Defense Mechanisms or cell- cycle Cycle The type of signal that ends the inspiratory phase delivered by the ventilator Invasive Mechanical Ventilation regulation. Peutz-Jeghers syndrome is caused by disruptions in the STK11 gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics and is associated with colonic (colorectal) and noncolonic (pancreatic, gastric, breast, uterine, cervical, lung, ovarian, and testicular) cancers. Management is with close surveillance Surveillance Developmental Milestones and Normal Growth and surgery.

Last updated: 17 Mar, 2022

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Contents

Overview

Definition

Peutz-Jeghers syndrome (PJS) is an autosomal-dominant inherited disorder defined by gastrointestinal, hamartomatous polyps, and skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions/mucosal melanin Melanin Insoluble polymers of tyrosine derivatives found in and causing darkness in skin (skin pigmentation), hair, and feathers providing protection against sunburn induced by sunlight. Carotenes contribute yellow and red coloration. Seborrheic Keratosis macules.

Epidemiology

  • Relatively rare
  • 1 case per 60,000–300,000
  • Median Median After arranging the data from loWest to highest, the median is the middle value, separating the lower half from the upper half of the data set. Measures of Central Tendency and Dispersion age for 1st presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor of polyps: 11–13 years old
  • Approximately 50% of people have symptoms by age 20.
  • 50%–80% of STK11 mutations are familial.
  • Both sexes are equally affected.
  • Cancer risk ↑ with age: 
    • 1%–2% risk by 20 years old
    • Approximately 30% by 50 years old
    • Approximately 80% by 70 years old
  • 15x ↑ risk of developing intestinal cancer

Etiology

  • Autosomal-dominant inherited-germline mutation Mutation Genetic mutations are errors in DNA that can cause protein misfolding and dysfunction. There are various types of mutations, including chromosomal, point, frameshift, and expansion mutations. Types of Mutations of the serine Serine A non-essential amino acid occurring in natural form as the l-isomer. It is synthesized from glycine or threonine. It is involved in the biosynthesis of purines; pyrimidines; and other amino acids. Synthesis of Nonessential Amino Acids/threonine kinase 11 (STK11/LBT1) tumor Tumor Inflammation-suppressor gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics on chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 19p13
  • STK11 mutation Mutation Genetic mutations are errors in DNA that can cause protein misfolding and dysfunction. There are various types of mutations, including chromosomal, point, frameshift, and expansion mutations. Types of Mutations: associated with 50%–80% of families diagnosed with PJS

Pathophysiology

  • Functions of tumor Tumor Inflammation– suppression Suppression Defense Mechanisms and cell- cycle Cycle The type of signal that ends the inspiratory phase delivered by the ventilator Invasive Mechanical Ventilation regulation of the STK11/LKB1 gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics are compromised.
  • Encodes for multifunctional serine Serine A non-essential amino acid occurring in natural form as the l-isomer. It is synthesized from glycine or threonine. It is involved in the biosynthesis of purines; pyrimidines; and other amino acids. Synthesis of Nonessential Amino Acids/threonine kinase (STK), which is important in 2nd-messenger signal transduction Transduction The transfer of bacterial DNA by phages from an infected bacterium to another bacterium. This also refers to the transfer of genes into eukaryotic cells by viruses. This naturally occurring process is routinely employed as a gene transfer technique. Bacteriology
  • STK modulation:
    • Cellular proliferation
    • Cell polarity
    • Important role in responding to ↓ cellular energy levels
  • STK11 protein → inhibition of AMP-activated protein kinase Protein kinase A family of enzymes that catalyze the conversion of ATP and a protein to adp and a phosphoprotein. Interferons (AMPK) → signals the inhibition of the mechanistic target of rapamycin kinase (mTOR)
  • In PJS, the mTOR pathway is dysregulated.
  • Polyps are caused by an overgrowth of cells native to the normally occurring area:
    •  Hamartomatous polyps are composed of normal cellular elements of the GI tract.
    • The PJS type of hamartomatous polyp is microscopically differentiated by:
      • The extensive smooth muscle proliferation, and
      • The unique, arborizing pattern throughout the polyp

Clinical Presentation

History

  • Parents may report perioral and buccal macules, which 1st appear around 5 years of age.
  • Family history Family History Adult Health Maintenance of PJS
  • During the 1st 3 decades of life:
    • Anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types
    • Rectal bleeding
    • Abdominal pain Abdominal Pain Acute Abdomen
    • Obstruction
    • Intussusception Intussusception Intussusception occurs when a part of the intestine (intussusceptum) telescopes into another part (intussuscipiens) of the intestine. The condition can cause obstruction and, if untreated, progress to bowel ischemia. Intussusception is most common in the pediatric population, but is occasionally encountered in adults. Intussusception

Physical examination

  • Mucocutaneous pigment and melanin Melanin Insoluble polymers of tyrosine derivatives found in and causing darkness in skin (skin pigmentation), hair, and feathers providing protection against sunburn induced by sunlight. Carotenes contribute yellow and red coloration. Seborrheic Keratosis macules in lips Lips The lips are the soft and movable most external parts of the oral cavity. The blood supply of the lips originates from the external carotid artery, and the innervation is through cranial nerves. Lips and Tongue: Anatomy, perioral area, buccal mucosa Buccal mucosa Oral Cancer, eyes, nostrils, fingertips, palms, soles, and perianal areas:
    • 1–5 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma macules
    • Present in more than 95% of cases
    • Small, flat, brown, or dark-blue spots
    • Similar in appearance to freckles Freckles Primary Skin Lesions
    • Most commonly around the:
      • Mouth crossing the vermilion border: 94%
      • Nostrils
      • Perianal area
      • Digits
      • Dorsal and volar aspects of hands and feet: 62%–74%
    • May fade after puberty Puberty Puberty is a complex series of physical, psychosocial, and cognitive transitions usually experienced by adolescents (11-19 years of age). Puberty is marked by a growth in stature and the development of secondary sexual characteristics, achievement of fertility, and changes in most body systems. Puberty, but tend to persist in the buccal mucosa Buccal mucosa Oral Cancer
  • Rectal polyps may be found during a rectal examination.
  • Gynecomastia Gynecomastia Gynecomastia is a benign proliferation of male breast glandular ductal tissue, usually bilateral, caused by increased estrogen activity, decreased testosterone activity, or medications. The condition is common and physiological in neonates, adolescent boys, and elderly men. Gynecomastia and growth acceleration (due to Sertoli-cell tumor Tumor Inflammation)
  • Testicular mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast
Mucocutaneous pigment macules in a very young patient

Mucocutaneous pigment macules in a young patient

Image: “Peutz-Jeghers syndrome: black spots localized in the perioral area” by Rogério O. Gondak, et al AL Amyloidosis. License: CC BY 4.0

Diagnosis

  • Diagnosis requires 2 of the following:
    • ≥ 2 PJS polyps on histology
    • Family history Family History Adult Health Maintenance of PJS
    • Characteristic mucocutaneous pigmentation ( lips Lips The lips are the soft and movable most external parts of the oral cavity. The blood supply of the lips originates from the external carotid artery, and the innervation is through cranial nerves. Lips and Tongue: Anatomy, mouth, nose Nose The nose is the human body’s primary organ of smell and functions as part of the upper respiratory system. The nose may be best known for inhaling oxygen and exhaling carbon dioxide, but it also contributes to other important functions, such as tasting. The anatomy of the nose can be divided into the external nose and the nasal cavity. Nose and Nasal Cavity: Anatomy, eyes, fingers, genitalia)
  • PJS polyps do not have specific features on endoscopy Endoscopy Procedures of applying endoscopes for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. Transluminal, to examine or perform surgery on the interior parts of the body. Gastroesophageal Reflux Disease (GERD) and can only be reliably distinguished from other types of polyps by histopathology.
    • Polyps (60%–90%) are most commonly found in the small intestine Small intestine The small intestine is the longest part of the GI tract, extending from the pyloric orifice of the stomach to the ileocecal junction. The small intestine is the major organ responsible for chemical digestion and absorption of nutrients. It is divided into 3 segments: the duodenum, the jejunum, and the ileum. Small Intestine: Anatomy ( jejunum Jejunum The middle portion of the small intestine, between duodenum and ileum. It represents about 2/5 of the remaining portion of the small intestine below duodenum. Small Intestine: Anatomy).
    • Others are in the colon Colon The large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy (50%–64%) and in the stomach Stomach The stomach is a muscular sac in the upper left portion of the abdomen that plays a critical role in digestion. The stomach develops from the foregut and connects the esophagus with the duodenum. Structurally, the stomach is C-shaped and forms a greater and lesser curvature and is divided grossly into regions: the cardia, fundus, body, and pylorus. Stomach: Anatomy (15%–30%).
    • Polyps can be sessile, lobulated, or pedunculated.
    • Pathology: distinct arborization pattern of smooth muscle into the lamina propria Lamina propria Whipple’s Disease
  • Genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies is recommended for individuals meeting the diagnostic criteria:
    • Helps identify relatives at risk
    • Genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies can be used for confirmation of PJS:
      • Variable Variable Variables represent information about something that can change. The design of the measurement scales, or of the methods for obtaining information, will determine the data gathered and the characteristics of that data. As a result, a variable can be qualitative or quantitative, and may be further classified into subgroups. Types of Variables sensitivity Sensitivity Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Blotting Techniques of the test
      • Familial cases: 70%
      • Sporadic Sporadic Selective IgA Deficiency cases: 30%–67%
    • Not all PJS-associated mutations have been identified; absence of STK11 mutation Mutation Genetic mutations are errors in DNA that can cause protein misfolding and dysfunction. There are various types of mutations, including chromosomal, point, frameshift, and expansion mutations. Types of Mutations does not exclude a PJS diagnosis.
Solitary peutz-jeghers type hamartomatous polyps

Solitary hamartomatous polyps typical of Peutz-Jeghers syndrome

Image: “Pedunculated duodenal polyp measuring 15 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma in diameter in the second part of the duodenum Duodenum The shortest and widest portion of the small intestine adjacent to the pylorus of the stomach. It is named for having the length equal to about the width of 12 fingers. Small Intestine: Anatomy” by Yusuke Sekino, et al AL Amyloidosis. License: CC BY 2.0

Management

Observation

  • Extend genetic counseling Genetic Counseling An educational process that provides information and advice to individuals or families about a genetic condition that may affect them. The purpose is to help individuals make informed decisions about marriage, reproduction, and other health management issues based on information about the genetic disease, the available diagnostic tests, and management programs. Psychosocial support is usually offered. Myotonic Dystrophies to patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship and their families (especially patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship wishing to have children).
  • Annual examination and CBC (checking for iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements deficiency anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types)
  • Endoscopy Endoscopy Procedures of applying endoscopes for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. Transluminal, to examine or perform surgery on the interior parts of the body. Gastroesophageal Reflux Disease (GERD): 
    • Includes esophagogastroduodenoscopy and video capsule Capsule An envelope of loose gel surrounding a bacterial cell which is associated with the virulence of pathogenic bacteria. Some capsules have a well-defined border, whereas others form a slime layer that trails off into the medium. Most capsules consist of relatively simple polysaccharides but there are some bacteria whose capsules are made of polypeptides. Bacteroides endoscopy Endoscopy Procedures of applying endoscopes for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. Transluminal, to examine or perform surgery on the interior parts of the body. Gastroesophageal Reflux Disease (GERD)
    • Beginning at 8 years old
    • If polyps are found, repeat every 2–3 years.
    • If without polyps, repeat at age 18 or earlier if symptomatic
  • Colonoscopy Colonoscopy Endoscopic examination, therapy or surgery of the luminal surface of the colon. Colorectal Cancer Screening: 
    • Beginning at 8 years old
    • If polyps are found, repeat every 2–3 years.
    • If without polyps, repeat at age 18 or earlier if symptoms
  • Screening Screening Preoperative Care for pancreatic cancer:
    • MRCP MRCP Non-invasive diagnostic technique for visualizing the pancreatic ducts and bile ducts without the use of injected contrast media or x-ray. Mri scans provide excellent sensitivity for duct dilatation, biliary stricture, and intraductal abnormalities. Primary Sclerosing Cholangitis or endoscopic ultrasound 
    • Beginning at 30–35 years old, repeating every 1–2 years
  • Breast cancer Breast cancer Breast cancer is a disease characterized by malignant transformation of the epithelial cells of the breast. Breast cancer is the most common form of cancer and 2nd most common cause of cancer-related death among women. Breast Cancer screening Screening Preoperative Care:
    • Clinical examination: beginning at 30 years old, repeating every 6 months
    • Mammogram Mammogram Fibrocystic Change and breast MRI: beginning at 25–30 years old
  • Screening Screening Preoperative Care for cervical, ovarian, and endometrial cancer Endometrial Cancer Endometrial carcinoma (EC) is the most common gynecologic malignancy in the developed world, and it has several histologic types. Endometrioid carcinoma (known as type 1 EC) typically develops from atypical endometrial hyperplasia, is hormonally responsive, and carries a favorable prognosis. Endometrial Hyperplasia and Endometrial Cancer:
    • Pap smear Pap smear Cytological preparation of cells collected from a mucosal surface and stained with Papanicolaou stain. Cervical Cancer Screening and pelvic exam: annually starting at age 18
    • Observe for signs of precocious puberty Puberty Puberty is a complex series of physical, psychosocial, and cognitive transitions usually experienced by adolescents (11-19 years of age). Puberty is marked by a growth in stature and the development of secondary sexual characteristics, achievement of fertility, and changes in most body systems. Puberty.
    • Recommendations for transvaginal ultrasound Transvaginal Ultrasound Obstetric Imaging vary.
  • Screening Screening Preoperative Care for testicular tumors (Sertoli cell tumor Tumor Inflammation):
    • Annual testicular examination: beginning at 10 years old
    • Also check for signs of feminization (e.g., gynecomastia Gynecomastia Gynecomastia is a benign proliferation of male breast glandular ductal tissue, usually bilateral, caused by increased estrogen activity, decreased testosterone activity, or medications. The condition is common and physiological in neonates, adolescent boys, and elderly men. Gynecomastia)
    • Obtain US if abnormalities are noted
  • Risk for thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy and lung cancer Lung cancer Lung cancer is the malignant transformation of lung tissue and the leading cause of cancer-related deaths. The majority of cases are associated with long-term smoking. The disease is generally classified histologically as either small cell lung cancer or non-small cell lung cancer. Symptoms include cough, dyspnea, weight loss, and chest discomfort. Lung Cancer is present in PJS, but screening Screening Preoperative Care lacks supporting evidence.

Surgical management

  • Endoscopic polypectomy for polyps > 0.3 cm
  • Prophylactic mastectomy Mastectomy Surgical procedure to remove one or both breasts. Fat Necrosis of the Breast 
  • Prophylactic hysterectomy and bilateral salpingo-oophorectomy after completion of childbearing
  • Other surgeries include laparotomies and laparoscopies for GI involvement and extraintestinal complications. 
  • Laparotomy Laparotomy Incision into the side of the abdomen between the ribs and pelvis. Laparotomy and Laparoscopy and resection may be necessary for:
    • Neoplastic changes
    • Inability to monitor and remove polyps
    • Intussusception Intussusception Intussusception occurs when a part of the intestine (intussusceptum) telescopes into another part (intussuscipiens) of the intestine. The condition can cause obstruction and, if untreated, progress to bowel ischemia. Intussusception is most common in the pediatric population, but is occasionally encountered in adults. Intussusception
    • Obstruction
    • Persistent intestinal bleeding

Complications

  • Intussusception Intussusception Intussusception occurs when a part of the intestine (intussusceptum) telescopes into another part (intussuscipiens) of the intestine. The condition can cause obstruction and, if untreated, progress to bowel ischemia. Intussusception is most common in the pediatric population, but is occasionally encountered in adults. Intussusception in 69% of individuals
  • GI obstruction by polyps in the small and large bowel in 43% of individuals
  • Mesenteric ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage in 23% of individuals
  • Iron Iron A metallic element with atomic symbol fe, atomic number 26, and atomic weight 55. 85. It is an essential constituent of hemoglobins; cytochromes; and iron-binding proteins. It plays a role in cellular redox reactions and in the transport of oxygen. Trace Elements-deficiency anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types
  • GI bleeding from ulcerations in 14% of individuals
  • Extrusion of polyp in 7% of individuals

Prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas

  • 39% lifetime risk of colorectal cancer Colorectal cancer Colorectal cancer (CRC) is the 2nd leading cause of cancer-related deaths in the United States. Colorectal cancer is a heterogeneous disease that arises from genetic and epigenetic abnormalities, with influence from environmental factors. Colorectal Cancer
  • 32%–54% lifetime risk of breast cancer Breast cancer Breast cancer is a disease characterized by malignant transformation of the epithelial cells of the breast. Breast cancer is the most common form of cancer and 2nd most common cause of cancer-related death among women. Breast Cancer
  • Approximately 50% of individuals with PJS die from cancer by 57 years of age.
  • Mean Mean Mean is the sum of all measurements in a data set divided by the number of measurements in that data set. Measures of Central Tendency and Dispersion age of 1st cancer diagnosis: 43 years old

Differential Diagnosis

  • Cowden disease: an autosomal-dominant disorder caused by mutations in PTEN, a tumor Tumor Inflammation-suppressor gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics. Cowden disease is a genodermatosis and characterized by multiple, benign Benign Fibroadenoma hamartomas (in any location), mucocutaneous lesions, and macrocephaly Macrocephaly Cowden Syndrome. Management depends on the location of the hamartoma Hamartoma A focal malformation resembling a neoplasm, composed of an overgrowth of mature cells and tissues that normally occur in the affected area. Colorectal Cancer. 
  • Hereditary nonpolyposis colon Colon The large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy cancer ( HNPCC HNPCC Lynch syndrome, also called hereditary non-polyposis colorectal cancer (HNPCC), is the most common inherited colon cancer syndrome, and carries a significantly increased risk for endometrial cancer and other malignancies. Lynch syndrome has an autosomal dominant inheritance pattern involving pathogenic variants in one of the mismatch repair (MMR) genes or epithelial cell adhesion molecule (EpCAM). Lynch syndrome): an autosomal-dominant disorder caused by mutations in the mismatch repair Mismatch repair A DNA repair pathway involved in correction of errors introduced during DNA replication when an incorrect base, which cannot form hydrogen bonds with the corresponding base in the parent strand, is incorporated into the daughter strand. Exonucleases recognize the base pair mismatch and cause a segment of polynucleotide chain to be excised from the daughter strand, thereby removing the mismatched base. Lynch syndrome ( MMR MMR A DNA repair pathway involved in correction of errors introduced during DNA replication when an incorrect base, which cannot form hydrogen bonds with the corresponding base in the parent strand, is incorporated into the daughter strand. Excinucleases recognize the base pair mismatch and cause a segment of polynucleotide chain to be excised from the daughter strand, thereby removing the mismatched base. Lynch syndrome) genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure, leading to the development of colorectal cancer Colorectal cancer Colorectal cancer (CRC) is the 2nd leading cause of cancer-related deaths in the United States. Colorectal cancer is a heterogeneous disease that arises from genetic and epigenetic abnormalities, with influence from environmental factors. Colorectal Cancer in 1st-degree relatives. Hereditary nonpolyposis colon Colon The large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy cancer is also known as Lynch syndrome Lynch syndrome Lynch syndrome, also called hereditary non-polyposis colorectal cancer (HNPCC), is the most common inherited colon cancer syndrome, and carries a significantly increased risk for endometrial cancer and other malignancies. Lynch syndrome has an autosomal dominant inheritance pattern involving pathogenic variants in one of the mismatch repair (MMR) genes or epithelial cell adhesion molecule (EpCAM). Lynch syndrome. Management is with prophylactic colectomy and frequent endoscopy Endoscopy Procedures of applying endoscopes for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. Transluminal, to examine or perform surgery on the interior parts of the body. Gastroesophageal Reflux Disease (GERD) for surveillance Surveillance Developmental Milestones and Normal Growth. 
  • Juvenile polyposis: an autosomal-dominant condition characterized by the growth of hamartomatous polyps (juvenile type) in the colon Colon The large intestines constitute the last portion of the digestive system. The large intestine consists of the cecum, appendix, colon (with ascending, transverse, descending, and sigmoid segments), rectum, and anal canal. The primary function of the colon is to remove water and compact the stool prior to expulsion from the body via the rectum and anal canal. Colon, Cecum, and Appendix: Anatomy. Juvenile polyposis is commonly associated with mutations in the SMAD4 and BMPR1A BMPR1A A subtype of bone morphogenetic protein receptors with high affinity for bone morphogenetic proteins. They can interact with and undergo phosphorylation by type II bone morphogenetic protein receptors. They signal primarily through receptor-regulated SMAD proteins. Familial Juvenile Polyposis genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure. Diagnosis is made by visualization of > 5 polyps on colonoscopy Colonoscopy Endoscopic examination, therapy or surgery of the luminal surface of the colon. Colorectal Cancer Screening, juvenile polyps in other areas of the GI tract, or any number of polyps plus a positive family history Family History Adult Health Maintenance. Management includes surveillance Surveillance Developmental Milestones and Normal Growth, polypectomy, and colectomy in cases of symptomatic GI neoplasia, increased polyps, and confirmed CRC. 
  • Colorectal cancer Colorectal cancer Colorectal cancer (CRC) is the 2nd leading cause of cancer-related deaths in the United States. Colorectal cancer is a heterogeneous disease that arises from genetic and epigenetic abnormalities, with influence from environmental factors. Colorectal Cancer (CRC): the 2nd leading cause of cancer-related deaths in the United States. Colorectal cancer Colorectal cancer Colorectal cancer (CRC) is the 2nd leading cause of cancer-related deaths in the United States. Colorectal cancer is a heterogeneous disease that arises from genetic and epigenetic abnormalities, with influence from environmental factors. Colorectal Cancer is a heterogeneous disease, arising from genetic and epigenetic abnormalities, with influence from environmental factors. Almost all cases of CRC are adenocarcinoma. Because most cases are asymptomatic, screening Screening Preoperative Care is important. Diagnosis is by colonoscopy Colonoscopy Endoscopic examination, therapy or surgery of the luminal surface of the colon. Colorectal Cancer Screening and management is primarily surgical.
  • Thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy cancer: malignancy Malignancy Hemothorax of the thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy-gland cells arising from thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy follicular cells or calcitonin Calcitonin A peptide hormone that lowers calcium concentration in the blood. In humans, it is released by thyroid cells and acts to decrease the formation and absorptive activity of osteoclasts. Its role in regulating plasma calcium is much greater in children and in certain diseases than in normal adults. Other Antiresorptive Drugs-producing C cells C cells Calcium Hemostasis and Bone Metabolism. Papillary cancer is the most common type associated with familial adenomatous polyposis Familial Adenomatous Polyposis Familial adenomatous polyposis (FAP) is an autosomal dominant inherited genetic disorder that presents with numerous adenomatous polyps in the colon. Familial adenomatous polyposis is the most common of the polyposis syndromes, which is a group of inherited or acquired conditions characterized by the growth of polyps in the GI tract, associated with other extracolonic features. Familial Adenomatous Polyposis ( FAP FAP Familial adenomatous polyposis (FAP) is an autosomal dominant inherited genetic disorder that presents with numerous adenomatous polyps in the colon. Familial adenomatous polyposis is the most common of the polyposis syndromes, which is a group of inherited or acquired conditions characterized by the growth of polyps in the GI tract, associated with other extracolonic features. Familial Adenomatous Polyposis). Exposure Exposure ABCDE Assessment to ionizing radiation Radiation Emission or propagation of acoustic waves (sound), electromagnetic energy waves (such as light; radio waves; gamma rays; or x-rays), or a stream of subatomic particles (such as electrons; neutrons; protons; or alpha particles). Osteosarcoma and iodine Iodine A nonmetallic element of the halogen group that is represented by the atomic symbol I, atomic number 53, and atomic weight of 126. 90. It is a nutritionally essential element, especially important in thyroid hormone synthesis. In solution, it has anti-infective properties and is used topically. Thyroid Hormones deficiency are also risk factors. Diagnosis is with thyroid Thyroid The thyroid gland is one of the largest endocrine glands in the human body. The thyroid gland is a highly vascular, brownish-red gland located in the visceral compartment of the anterior region of the neck. Thyroid Gland: Anatomy-stimulating hormone, ultrasound, and biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma. Management is mainly surgical. 

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Peutz-Jegher’s Syndrome, Juvenile Polyposis and HNPCC

References

  1. Gondak, R. O., et al. (2012). Oral pigmented lesions: Clinicopathologic features and review of the literature. Medicina oral, patologia oral y cirugia bucal. 17(6), e919–e924. https://pubmed.ncbi.nlm.nih.gov/22549672/
  2. Sekino, Y., et al. (2011). Solitary Peutz-Jeghers type hamartomatous polyps in the duodenum are not always associated with a low risk of cancer: two case reports. Journal of medical case reports. 5, 240. https://pubmed.ncbi.nlm.nih.gov/21707968/
  3. Chung, D. (2021). Peutz-Jeghers syndrome: Clinical manifestations, diagnosis, and management. UpToDate. Retrieved June 14, 2021, from https://www.uptodate.com/contents/peutz-jeghers-syndrome-clinical-manifestations-diagnosis-and-management
  4. Wu, M., Krishnamurthy, K. (2021). Peutz-jeghers syndrome. StatPearls. Treasure Island (FL): StatPearls Publishing. Retrieved June 10, 2021, from http://www.ncbi.nlm.nih.gov/books/NBK535357/
  5. To, B. (2018). Peutz-Jeghers Syndrome. Emedicine. Retrieved June 14, 2021, from https://emedicine.medscape.com/article/182006-overview#a2
  6. Kopacova, M., et al. (2009). Peutz-Jeghers syndrome: Diagnostic and therapeutic approach. World J Gastroenterol. 15(43), 5397–5408. https://pubmed.ncbi.nlm.nih.gov/19916169/
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